Publications by authors named "R D Wijesekera"

High-purity (98.8%, TiO) rutile nanoparticles were successfully synthesized using ilmenite sand as the initial titanium source. This novel synthesis method was cost-effective and straightforward due to the absence of the traditional gravity, magnetic, electrostatic separation, ball milling, and smelting processes.

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We assessed the levels of Pb, Cd, and Mn in contour feathers of the feral pigeon (Columba livia) and house crow (Corvus splendens) obtained from five urban/suburban locations across Sri Lanka, using the AAS following wet digestion. Our key objectives were to compare accumulation levels in the two avian species with different foraging habits and living in common locations, and to establish baseline information on the presence of these metals in multiple locations in Sri Lanka with varying levels of urbanization. Owing to reservations that have been expressed by previous workers regarding the use of feathers for assessing heavy metal pollution, we first tested the efficacy of contour feathers by using our data for comparing the coefficients of variation in metal levels within and between locations.

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Weligama coconut leaf wilt disease (WCLWD) causes heavy losses in the coconut cultivations of southern Sri Lanka. The in-house developed and validated indirect ELISA was based on specific polyclonal antibodies raised in female New Zealand White rabbits, against partially purified WCLWD associated phytoplasma. This ELISA has the potential to distinguish secA PCR confirmed, WCLWD associated phytoplasma positive palms from phytoplasma free palms at high accuracy (93%) and sensitivity (92.

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This paper investigates the toxicity of cadmium (Cd) on young stages of the common Asian toad Duttaphrynus melanostictus (Schneider 1799). Signs of acute toxicity were evident in tadpoles repeatedly exposed to five concentrations ranging from 0.002 to 2 mg L(-1)of Cd which included environmentally relevant levels.

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